According to Johnstown Sgt. Patrick Goggin, the preteen approached the stand and pointed a gun at a 10-year-old boy, threatening to shoot if the other boys didn't hand over the money they had earned selling lemonade.
He was chased home by the victims while the police were alerted to the situation.
A subsequent investigation revealed that the weapon used in the heist was a toy, albeit a potentially dangerous one.
The boy is expected to face charges in juvenile court, though the outcome will likely remain confidential.